1. Field of the Invention
The present invention relates to an electroluminescent diode including a delayed florescence material and a quantum dot. More particularly, the present invention relates to an electroluminescent diode having a quantum dot in which luminous efficiency is improved using energy of a delayed florescence material.
2. Discussion of Related Art
A quantum dot (QD) is a semiconductor material with a crystalline structure having a size of several nanometers and has a characteristic of emitting light by itself through a quantum effect.
In particular, the number of free electrons is limited within a range of 1 to 100 because the QD has a large number of interior electrons but has a smaller size than an Exciton Bohr Radius thereof, energy levels of the electrons are limited to be discontinued, and the QD has electrical and optical characteristics different from that of a semiconductor which is in a bulk state forming a continuous band.
The QD can control an energy level thereof according to a size of the QD, and thus a band gap thereof can be controlled.
Accordingly, in a conventional organic light emitting diode (OLED) or the like, a type of organic material used therein should be changed in order to display different colors, but the QD has an advantage in that a simpler light emitter is manufactured because a color of emitted light is changed by controlling a size of the QD using the QD.
Further, a QD-electroluminescence diode has advantages of being capable of implementing a much more natural color with high color purity when compared to an active matrix organic light emitting diode (AMOLED), having a power consumption rate of about one-fifth of the AMOLED, having a relatively low cost, and being capable of being manufactured as a flexible display.
Due to the advantages described above, studies on an electroluminescent diode using a quantum dot are being actively conducted, but a problem in which a luminous efficiency of an electroluminescent diode using a quantum dot is low has not yet been solved even though continuous studies have been conducted.